Hi Steve, Metadata is data that does not contribute to an equality relationship. In most scenarios different types are considered not equal, and so should be modelled as data.
Stuart > > On Nov 14, 3:42 pm, Chouser <[EMAIL PROTECTED]> wrote: >> On Fri, Nov 14, 2008 at 2:11 PM, Jeff Rose <[EMAIL PROTECTED]> wrote: >>> Does my dispatch function have to inspect the passed in values to >>> figure out whichtypeof struct they are, or can I query that >>> somehow? >> >> My understanding is that StructMaps are just Maps with an >> implementation that's optimized to reduce memory usage. The >> different >> basis types don't really function as "classes" of StractMaps or >> anything. You can still add new keys to StructMaps, for example, >> just >> like any other Map. So if you want some kind of 'type'datado >> dispatch off of, you'll have to attach that yourself, either as >> another key that all your Maps share or as metadata. >> > I've actually got the same use case as Jeff Rose -- I want some > generic methods on algebraic data types. Is there any reason to prefer > a data field over a metadata field, or vice versa, for the type tag? > > -- Steve > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/clojure?hl=en -~----------~----~----~----~------~----~------~--~---
